Pushbutton switch operator with a reversible lockout

ABSTRACT

An enclosure structure including an operator for a pushbuttontype switch. The enclosure is of the dust or watertight type and supports a handle which is movable with an oscillating motion to an ON position and an OFF position to actuate either one of a pair of linearly movable switch operating buttons and a plate which is selectively mountable in either of two positions on a front wall of the enclosure to lock the operating handle in either the ON or OFF positions.

United States Patent [72] Inventors Lewis M. Lehman;

John R. Stauder, both of Milwaukee, Wis. [21] AppLNo. 9,161 [22] FiledFeb. 6, 1970 [45] Patented Oct. 5, 1971 [73] Assignee Square D CompanyPark Ridge, 1]].

[54] PUSIIBU'I'ION SWITCH OPERATOR WITH A REVERSIBLE LOCKOUT 10 Claims,5 Drawing Figs.

[52] US. Cl..-. 200/42 T, 200/ 172 A [51] Int.Cl H0lh 9/28 [50] Field ofSearch 200/42, 44, I 50 A, 172 A [56] References Cited UNITED STATESPATENTS 2,171,267 8/1939 Doty 200/172 A Primary ExaminerRobert K.Schaefer Assistant Examiner-William J. Smith Attorneys-Harold J. Rathbunand William H Schmeling ABSTRACT: An enclosure structure including anoperator for a pushbutton-type switch. The enclosure is of the dust orwatertight type and supports a handle which is movable with anoscillating motion to an ON position and an OFF position to actuateeither one of a pair of linearly movable switch operating buttons and aplate which is selectively mountable in either of two positions on afront wall of the enclosure to lock the operating handle in either theON or OFF positions 74 66 68 V 4 6 44 42 so 4 so 56 e g e5 48 A p l9E854 3s PATENTEDDBT 5mm 3 e10 849 I N VEN'I'OR.

JOHN R. STAUDER LEWIS M.LEHMAN PUSHBUTTON SWITCH OPERATOR WITH AREVERSIBLE LOCKOUT This invention relates to enclosures for switches andmore particularly to fluid-proof and dusttight enclosures or boxes whichmay be securely locked to prevent unauthorized operation of a switchwithin the enclosure from either the ON or the OFF positions.

Enclosures for electrical devices used in industrial operations havebeen standardized into various categories .to satisfy the serviceconditions imposed by the environment in which the devices areinstalled. The National Electrical Manufacturers Association (NEMA) hasdeveloped a NEMA 4 classification, commonly known as watertight, forenclosures which are particularly suited for use on ship docks and indams, breweries and the like, which shall meet the requirements of apredescribed hose test. Another NEMA classification, called NEMA I2, isdesignated for enclosures which have been designed for use in thoseindustries where it is desirable to exclude such materials as dust,lint, fibers and flyings, oil seepage or coolant seepage from within theenclosure.

One of the requisites of a dusttight and fluidtight switch enclosure isthat it must be dusttight and waterproof and provide an arrangementwhereby a switch within the enclosure may be actuated from the exteriorof the enclosure. A further requirement is that an arrangement beprovided to prevent the switch from being operated from either the ONposition or the OFF position. An arrangement provided for locking theswitch in the OFF position is included so that the switch may beprevented from being actuated to a circuit closing position and completea circuit to a motor which drives machinery while the machinery is beingserviced so as to prevent damage to the equipment or injury topersonnel. On occasion it is necessary that the continuity of circuitsbe continuously maintained. To satisfy this requirement, enclosures areprovided arrangements which will prevent the switch from being operatedto a circuit opening position by unauthorized personnel. An example ofan installation requiring this feature may occur in school buildingswherein switches are provided with a lock-on structure to preventmischievious students from interrupting the service to lights, fans andthe like.

Watertight and dusttight enclosures are well known and heretofore havebeen provided with rather complicated mechanisms for actuating theswitch within the enclosure from the exterior of the enclosure. Thestructure as herein disclosed is characterized by its pleasingappearance and a structure that is both economical to manufacture anddurable, so that it will withstand abuse that is normally encountered inindustrial environments. Additionally, the structure may be readilyserviced, is substantially tamper-proof and arranged to indicate theoperating condition of the switch within the enclosure from the exteriorof the enclosure. Further, the structure includes a simple lockoutmechanism which may be selectively positioned to maintain the switch ineither the OFF or ON circuit positions.

It is an object of the present invention to provide an enclosure for apushbutton switch that includes a lockout mechanism which may beselectively positioned to accept a padlock to prevent movement of theswitch operator from either the ON or the OFF circuit positions.

An additional object is to provide a switch enclosure with stops forexternal operating handle and a lockout structure that includes a platehaving a pair of openings therein which are arranged so that theposition of one of the openings may be reversed to accept a padlock andselectively lock a switch in either the ON or the OFF circuit positions.

A further object is to provide an operating mechanism for an enclosurewherein the operating mechanism includes a shaft having an externaloperator mounted on one end and a rotatable lever on the other end thatis arranged to engage and move the pushbuttons of the switch when theexternal operating handle is oscillated between two limiting positionsthat are provided by a cover for the switch.

A further object is to provide an operating mechanism for an enclosurewherein the operating mechanism includes a shaft having an externaloperator mounted on one end and a rotatable lever mounted on the otherend that is arranged to engage and move the pushbuttons of the switchwhen the external operating handle is oscillated between two limitingpositions that are provided by a cover for the switch and to maintainthe shaft within the enclosure by a C-n'ng that is received in a groovein the shaft so that the shaft may be readily withdrawn from theenclosure so that the position of a locking member which is selectivelypositionable to accept a padlock and lock the switch in either the OFFor the ON condition of operation may be readily changed.

Further objects and features of the invention will be readily apparentto those skilled in the art from the specification and appended drawingillustrating certain preferred embodiments in which:

FIG. 1 is a front elevational view of a switch enclosure incorporating aswitch actuating mechanism according to the present invention.

FIG. 2 is a cross-sectional view of the enclosure in FIG. 1 taken alongline 22 in FIG. 1.

FIG. 3 is a view of a portion of a switch enclosure in FIG. 1 with aportion thereof broken away to illustrate the relative operatingpositions of an operating handle and a lever which actuates a pair oflinearly movable buttons of the switch within the enclosure.

FIG. 4 is a view illustrating the enclosure operating handle in an ONcircuit position.

FIG. 5 is a plan view of a locking plate incorporated in the enclosurestructure in FIGS. 1 and 2.

A switch enclosure 10, as illustrated in the drawing, includes a base 12and a cover 14. The enclosure 10 defines an internal cavity 16 wherein aswitch 18 is mounted. The switch 18 is mounted on a rear wall 20 of thebase 12 which in turn may be mounted on a suitable vertical support wallor panel, not shown. The switch enclosure 10 is more clearly shown in anapplication for Design Pat., Ser. No. D2l,3l8, concurrently filedherewith which has been assigned by the inventors Lewis M. Lehman, JohnR. Stauder and David E. Scott to the assignee of the present invention.

The switch 18 is of the manually operated type and includes an OFFpushbutton 22 and an ON pushbutton 24 which are aligned in a plane 26that is perpendicular to the rear wall 20 and perpendicular to a top end28 and a bottom end 30 of the enclosure 10. The switch 18 as illustratedis of the type commonly known as a manually operated motor starter and,as illustrated, is of the form disclosed in an application for U.S. Pat,Ser. No. 9203, which has been assigned by the inventor Jordan F. Puetzto the assignee of the present invention. As disclosed in the Puetzapplication, the buttons 22 and 24 respectively have operating ends 32and 34 which are movable in a line of movement that extends in the plane26 so as to move a contact carrier and movable contacts within theswitch 18 from a position wherein the movable contacts are separatedfrom the stationary contacts of the switch 18 to a position wherein themovable contacts engage the stationary contacts so as to complete acircuit therebetween. Thus when the OFF pushbutton 22 is depressed, thecontacts of the switch 18 will be in an open circuit position and whenthe ON pushbutton 24 is depressed, the contacts of the switch 18 will bein a circuit closing position.

In the embodiment shown, the base 12 and the portion of the cover 14engaging the base 12 is formed of sheet metal. Positioned on an innerface of the cover 14 to engage edges of the base 12 is a sealing gasket36 which will prevent the entry of fluids and dust into the cavity 16when the cover 14 is secured to the base 12 by suitable fasteningdevices, not shown. The cover 14 is provided with a rectangular opening38 which occupies the area of the cover 14 in the vicinity of thepushbuttons 22 and 24. Positioned on the cover 14, so as to cover theopening 38, is a housing part 40 which is preferably formed of a diecast metal although if desired, the

housing part 40 may be formed of a suitable thermoplastic orthermosetting plastic material, all of which are well known to thoseskilled in the art. The housing part 40 is secured to the cover 14 bysuitable screws 41 and has a front wall 42 providing an external frontsurface 44 disposed at the exterior of the enclosure 10 and an internalsurface 46. The surfaces 44 and 46 each extend transversely of the plane26. The internal surface 46 is arranged to face and be spaced from theoperating ends 32 and 34 of the pushbuttons 22 and 24. The housing part40 has a left side 48 and a right side 50. each of which extend from thefront surface 44 to a rear surface 52. The rear surface 52 is arrangedto be secured to the front face of the cover 14. The front surface 44and the right side 50 are fonned to provide a generally triangularlyshaped indentation 54. The indentation 54 has a sidewall 56 extendingfrom the front surface 44 in a plane that is parallel and spaced fromthe plane 26. The portion of the indentation 54 adjacent the sidewall 56is provided with a generally triangularly shaped groove 58, most clearlyillustrated by FIGS. 2 and 4. Extending through the sidewall 56 from theexterior of the part 40 into the cavity 16 is a cylindrical bore 60. Thebore 60 extends along an axis that is perpendicular to the plane 26,equidistant between the lines of movement of the pushbuttons 22 and 24and spaced between the internal surface 46 and the ends 32 and 34 of thepushbuttons. Positioned by the bore 60 is a means 62 for selectivelymoving the pair of spaced pushbuttons 22 and 24 in their respectivelines of movement within the cavity 16 with a manual force that isapplied from the exterior of the enclosure 10.

The means 62 for selectively moving the pushbuttons 22 and 24 includes ashaft 64, a handle 66, a lever 68, an O-ring seal 70 and a C-ring 72.Additionally, the means 62 includes a means for selectively preventingthe movement of the handle 66 from one position to another positionwhich is illustrated in H6. as a locking plate 74 that has a pair ofopenings 76 and 78 located therein to function in a manner as will behereinafter described.

Extending inwardly into the cavity 16 and located on opposite sides ofthe plane 26 from the internal surface 46 are a pair of bosses 80 and82. The boss 80 has a cylindrical socket 84 which is centered on theaxis of the bore 60. The boss 82 has a free end wherein a hemisphericalgroove is disposed. The hemispherical groove similarly is centered onthe axis of the bore 60.

The shaft 64 has a length sufficient to permit a cylindrical portion 86on the left hand end of the shaft 64 to be joumaled within the socket 84while a portion, not shown, which has the handle 66 nonrotatably securedthereon, positions the handle 66 within the indentation 54. A portion 85of the shaft 64 received within the bore 60 is suitably grooved toreceive the O-ring seal 70. The O-ring seal 70 prevents the entrance offluids and dust from the exterior of the enclosure into the cavity 16. Aportion of the shaft 64 designated by a numeral 88 is shaped to providea nonrotatable connection between the shaft 64 and the lever 68 andpermit the shaft 64 to be detached from the lever 68. This result isaccomplished by truncating the opposite sides of the shaft 64 andproviding a similarly shaped bore 89 within the lever 68 which receivesthe shaft 64 so that the lever 68 and the shaft 64 may be separated bysliding the lever 68 on the shaft 64 and withdrawing the end portion 86from the bore 89. The lever 68 is positioned between the bosses 80 and82 to be rotated by the shaft 64. The truncated portions of the shaft 64are arranged so that the lever 68 extends substantially perpendicular tothe handle 66. The shaft is positioned against removal from the bore 60by the C-ring 72. The C-ring 72 is received in a suitable groove in theshaft 64 that is located in the shaft 64 so a surface of the C-ring 72is positioned adjacent the portion of wall 56 facing the cavity 16. Theremoval of the C-ring 72 from the groove 90 will permit the shaft 64 tobe slidably moved to the right in FIG. 2 as the portion 88 of the shaftslides in the noncircular bore 89 in the lever 68. The lever 68 has armportions 92 and 94 extending in substantially opposite directions fromthe shaft 64. As shown, the arms 92 and 94 are slightly inclined toprovide free ends 96 and 98 on the arms 92 and 94. The free ends 96 and98 are arranged to engage ends 32 and 34 to move the buttons 22 and 24in their respective lines of movement when the shaft 64 rotates betweentwo positions as dictated by the oscillating movement of the handle 66within the indentation 54.

As shown in FIG. 4, the triangularly shaped groove 58 which extends inthe plane perpendicular to the front surface 44 has a pair of sidewalls100 and 102 converging toward the rear wall 20. The walls 100 and 102are connected by a rounded apex 104. The plate 74 similarly has a pairof edges 106 and 108 and a rounded apex which are congruent with thewalls 100 and 102 and the apex 104 so that the plate 74 may be receivedin either of two selected positions in the groove 58. The opening 76 islocated in the plate 74 along a line that bisects the angle defined bythe edges 106 and 108 and is located to be aligned with the bore 60 topermit a portion of the shaft 64 to extend through the opening 76 whenthe locking plate 74 is in either of its two positions in the groove 58.The opening 78 is displaced from the bisecting line that extends throughthe opening 76 and is located so that at least a portion of the opening78 projects forwardly of the front surface 44 when the plate 74 is ineither of its two positions in the groove 58. Thus when the plate 74 ispositioned in the groove 58 in one of its selected positions, in amanner shown in FlG. 3, the opening 78 will be located to preventmovement of the operating handle 66 from the OFF position to the ONposition when the shackle of a padlock, not shown, is passed through theopening 78. Additionally, when the plate 74 is positioned in the groove58 in a manner illustrated in FIG. 4, the opening 78 will be located toreceive a shackle of a padlock and prevent the movement of the operatinghandle 66 from the ON position to the OFF position. The position of thelocking plate 74 in the groove 58 may be readily changed by merelyremoving the C-ring 72 from its groove in the shaft 64 so that theassembly consisting of the handle 66, the shaft 64, and the O-ring seal70 may be moved to the right in FIG. 2 as the portions of the shaft 64are withdrawn from the bore 60, the socket 84, the bore 89 and theopening 76 in the plate 74. When the shaft 64 and the handle 66 are thusremoved, the lever 68 will be detached from the shaft 64 and theposition of the locking plate may be reversed in the groove 58. Afterthe locking plate 74 is repositioned in the groove 58, the shaft 64 maybe reinserted through the opening 76 into the bore 60 and the bore 89 inthe lever 68 into its position wherein the portion 86 on the shaft isreceived in the socket 84. The shaft 64 together with the lever 68 andthe handle 66 are maintained assembled with the housing part 40 when theC-ring 72 is rein serted in the groove in the shaft 64 so that theswitch enclosure 10 may be readily converted to maintain the handle 66in either its ON position or its OFF position. in this connection itshould be noted that the opening 78, if properly positioned in the plate74, will prevent the movement of the handle 66 from its 0N and OFFpositions respectively when only a portion of the opening 78 isobstructed by an item smaller than the shackle of a padlock. Forexample, the diameter of a thin wire as used in wire-type seals, may beemployed and prevent the handle from moving from one of its selectedpositions to the other position as described.

While certain preferred embodiments of the invention have beenspecifically disclosed, it is understood that the invention is notlimited thereto, as many variations will be readily apparent to thoseskilled in the art and the invention is to be given its broadestpossible interpretation within the terms of the following claims.

What is claimed is:

1. An enclosure for a pushbutton switch, said switch having a pair ofspaced pushbuttons each having an operating end movable in a line ofmovement extending in a common plane, said enclosure including a parthaving a front wall providing an internal and an external surfaceextending in parallel planes that are transverse to the common planewith the internal surface of said part facing and spaced from theoperating ends of the pushbuttons, a sidewall extending in a directionof the switch from an edge of the front wall in a plane parallel andspaced from the common plane, and a bore extending through the sidewallalong an axis that is transverse to the common plane, equidistant to thelines of movement of the pushbuttons, and spaced between the rearsurface and the operating ends of the pushbuttons, a means forselectively moving the pair of spaced pushbuttons in their respectivelines of movement, said means including a shaft having a first portionrotatably joumaled in the bore, a second portion projecting from thesidewall externally of the enclosure part, and a third portion extendingin a space between the rear surface and the operating ends of thepushbuttons, a handle nonrotatably secured on the second portion of theshaft and ,movable between two positions for rotating the shaft with anoscillating movement between two positions, a lever nonrotatably securedon the third portion of of the shaft, said lever having arm portionsextending substantially in opposite directions to provide free ends onthe arms which are engageable with the operating ends of the buttons forselectively moving the buttons in their respective lines of movementwhen the handle is respectively moved to the two positions, and a meansincluding a platelike member mounted in either of two selected positionson the front wall, said platelike member having a pair of openingstherein respectively located to receive the shaft and a shackle of apadlock for selectively preventing movement of the handle from a firstof the two positions to a second of the two positions when the platelikemember is oriented in its first position and for preventing movement ofthe handle from the second position to the first position when theplatelike member is oriented in its second position.

2. The structure as recited in claim 1 including a V-shaped indentationextending from the edge into portions of the front surface and sidewall,said indentation having a shape to provide a recess for portions of thehandle and stops for limiting movement of the handle to the twopositions.

3. The structure as recited in claim 2 including a groove in the shaftthat is located between the first and the third portions of the shaftand a C-shaped ring removably received in the groove to rotatablyposition the shaft in the enclosure part.

4. The structure as recited in claim 3 including a second groove locatedin the first portion of the shaft and an O-ring seal in the secondgroove.

5. The structure as recited in claim 2 wherein the V-shaped indentationincludes a V-shaped slotted portion that is arranged to position theplatelike member in either the first or the second position.

6. The structure as recited in claim 5 wherein the platelike member hasgenerally a triangular shape with the comers of the triangle rounded.

7. The structure as recited in claim 1 wherein a pair of spaced supportsextending from the internal surface provide a support for the thirdportion of the shaft.

8. The structure as recited in claim 7 wherein the supports are spacedto position the lever on the third portion of the shaft.

9. The structure as recited in claim 8 wherein one of the supports isprovided with a cylindrical bearing to receive a cylindrical end on thethird portion and the other of the pair of supports is provided with ahemispherical bearing surface and the cylindrical bearing and thehemispherical bearing surface have a radius of curvature centered on anaxis of the bore.

10. The structure as recited in claim I wherein the enclosure is formedof a die cast metal and includes a rear edge that is positioned on asheet metal cover for the enclosure.

1. An enclosure for a pushbutton switch, said switch having a pair ofspaced pushbuttons each having an operating end movable in a line ofmovement extending in a common plane, said enclosure including a parthaving a front wall providing an internal and an external surfaceextending in parallel planes that are transverse to the common planewith the internal surface of said part facing and spaced from theoperating ends of the pushbuttons, a sidewall extending in a directionof the switch from an edge of the front wall in a plane parallel andspaced from the common plane, and a bore extending through the sidewallalong an axis that is transverse to the common plane, equidistant to thelines of movement of the pushbuttons, and spaced between the rearsurface and the operating ends of the pushbuttons, a means forselectively moving the pair of spaced pushbuttons in their respectivelines of movement, said means including a shaft having a first portionrotatably journaled in the bore, a second portion projecting from thesidewall externally of the enclosure part, and a third portion extendingin a space between the rear surface and the operating ends of thepushbuttons, a handle nonrotatably secured on the second portion of theshaft and movable between two positions for rotating the shaft with anoscillating movement between two positions, a lever nonrotatably securedon the third portion of of the shaft, said lever having arm portionsextending substantially in opposite directions to provide free ends onthe arms which are engageable with the operating ends of the buttons forselectively moving the buttons in their respective lines of movementwhen the handle is respectively moved to the two positions, and a meansincluding a platelike member mounted in either of two selected positionson the front wall, said platelike member having a pair of openingstherein respectively located to receive the shaft and a shackle of apadlock for selectively preventing movement of the handle from a firstof the two positions to a second of the two positions when the platelikemember is oriented in its first position and for preventing movement ofthe handle from the second position to the first position when theplatelike member is oriented in its second position.
 2. The structure asrecited in claim 1 including a V-shaped indentation extending from theedge into portions of the front surface and sidewall, said indentationhaving a shape to provide a recess for portions of the handle and stopsfor limiting movement of the handle to the two positions.
 3. Thestructure as recited in claim 2 including a groove in the shaft that islocated between the first and the third portions of the shaft and aC-shaped ring removably received in the groove to rotatably position theshaft in the enclosure part.
 4. The structure as recited in claim 3including a second groove located in the first portion of the shaft andan O-ring seal in the second groove.
 5. The structure as recited inclaim 2 wherein the V-shaped indentation includes a V-shaped slottedportion that is arranged to position the platelike member in either thefirst or the second position.
 6. The structure as recited in claim 5wherein the platelike member has generally a triangular shape with thecorners of the triangle rounded.
 7. The structure as recited in claim 1wherein a pair of spaced supports extending from the internal surfaceprovide a support for the third portion of the shaft.
 8. The structureas recited in claim 7 wherein the supports are spaced to position thelever on the third portion of the shaft.
 9. The structure as recited inclaim 8 wherein one of the supports is provided with a cylindricalbearing to receive a cylindrical end on the third portion and the otherof the pair of supports is provided with a hemispherical bearing surfaceand the cylindrical bearing and the hemispherical bearing surface have aradius of curvature centered on an axis of the bore.
 10. The structureas recited in claim 1 wherein the enclosure is formed of a die castmetal and includes a rear edge that is positioned on a sheet metal coverfor the enclosure.